This Asthma and Allergic Disease Center proposal deals with three aspects of allergic inflammation: (1) the functions of eosinophils, (2) the regulation of IgE antibodies and (3) IgE-induced late reactions. Concerning the study of eosinophils, we will determine the subcellular origin of the Charot-Leyden crystal (CLC) and we will isolate and determine the chemical compositions of the crystalline core of the eosinophil granule. We describe experiments to isolate and characterize the osmiophilic bodies in eosinophils. Finally, we will prepare antisera to the CLC and the eosinophil major basic proteins and establish radioimmunoassays for these substances. Concerning IgE antibodies, we will determine the comparative avidities of IgE antibodies to ragweed antigen E (AgE) and investigate the effect of nasal administration of ragweed antigens as a form of immunotherapy. We further propose to establish an animal model for ragweed sensitivity using inbred rats. We also will determine the heterogeneity of the IgE immune response to bee venom antigens and the effect of repeated parenteral administration of venom antigens in beekeepers. Lastly, the primary sequence of AgE and the chemical structure of the antigenic determinants of AgE will be defined. Concerning IgE-induced late inflammatory reactions, we will determine whether these occur in the nose and bronchi, investigate the type of lymphocytes in the inflamed tissue and the mediators involved and finally establish an animal model for the late reactions.